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A fluorescent light uses a lining to emit visible light, explain why this is necessary and how it works.

The vapour inside a fluorescent tube is excited and ionised by the electrode either end of the tubes. The excited electrons inside of the vapour are unstable and so decay into lower energy states. The dif...

Answered by Monty C. • Physics tutor

1661 Views

Find an expression for the escape velocity of a test object.

Escape velocity is the velocity required to just escape the gravitational pull of a body. The gravitational force of a body is given by Newtons Law:
F = GMm / r² (where G is the gra...

Answered by Ciara N. • Physics tutor

1899 Views

A motor does 4.8kJ of work in 2 minutes. What is its power output?

Power is the RATE of work done or energy transferred.
By the Law of Conservation of Energy, energy cannot be created or destroyed, only converted from one form to another. Power is the rate at which ...

Answered by Simran J. • Physics tutor

9690 Views

Suppose a student wants calculate the density of the two different objects, a metal cube and a small statue. Describe the methods the student could use to measure the density of the two objects.

First we should quickly remind ourselves of the equation for density:density= mass/ volumeTo calculate the density we need a method of measuring the mass of each object and another method for measuring th...

Answered by Alexander A. • Physics tutor

15599 Views

Imagine a probe in space. Argon gas can be fired from the probes fuel tanks to propel the probe. Discuss whether conservation of momentum applies and whether the speed of the probe increases.

With these long answer questions the examiners want to see both the quality of your English and your knowledge of the topic. Typically, this means using key words and phrases. The numbers in the brackets ...

Answered by Aran M. • Physics tutor

1575 Views